/*
 * Copyright 2020-2030 the original author or authors.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      https://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package com.extraty.question1048;

import lombok.Generated;

import java.util.Arrays;
import java.util.Comparator;

/**
 * @author Created by Neil Wang
 * @version 1.0.0
 * @date 2021/9/2 4:11 下午
 */
public class Solution1 {
    public int longestStrChain(String[] words) {
        Arrays.sort(words, Comparator.comparingInt(String::length));
        int length = words.length;
        int[] dynamicPlanning = new int[length];
        for (int i = 0; i < length - 1; i++) {
            for (int j = i + 1; j < length; j++) {
                if (isPredecessor(words[i], words[j]))
                    dynamicPlanning[j] = refreshPredecessorCounts(dynamicPlanning[i], dynamicPlanning[j]);
            }
        }
        return Arrays.stream(dynamicPlanning).max().getAsInt() + 1;
    }

    private int refreshPredecessorCounts(int i, int b) {
        return Math.max(i + 1, b);
    }

    @Generated
    private boolean isPredecessor(String a, String b) {
        if (b.length() - a.length() != 1) return false;
        int flag = 0;
        int i = 0;
        int j = 0;
        while (i < a.length() && j < b.length()) {
            if (a.charAt(i) == b.charAt(j)) {
                i++;
                j++;
            } else {
                flag++;
                j++;
                if (flag > 1) return false;
            }
        }
        return true;
    }
}
